At present it is known to carry out a single pressure test or cyclic pressure tests for detecting leakages in the dialysis fluid system. As a rule, they take place before a treatment. It is a drawback in this context that leakages occurring as late as during treatment cannot be detected or can be detected as late as during the preparation of a subsequent treatment. Carrying out cyclic pressure tests during a treatment disadvantageously results in delays of the course of therapy and thus in an efficient reduction of the duration of therapy, which has to be compensated by longer treatment periods for each patient. In general, it is a drawback that the accuracy in pressure tests is dependent on the amount of pressure as well as the pressure dwell time, which may question the reliability of the established values.
Furthermore, from the state of the art solutions are known in which leakage fluid is collected in an appropriate reservoir of the dialysis machine. The liquid level in the reservoir is detected via a fill level sensor or the like. It is a drawback in these solutions that apart from dialysis fluid escaping from the system further fluid such as condensation water may accumulate in the reservoir, thus resulting in errors in determining the quantity of dialysis fluid escaped from the system. Also in the inverse case that it is not the total quantity of dialysis fluid escaped from the system due to leakage which is collected in the container, for example because a particular share thereof evaporates, errors occur when the quantity escaped from the system is determined.
Basically state-of-the-art leakage detection is somewhat unsecure and inaccurate. There is the risk that minor leakage points that may already have serious effects depending on the patient are not yet or only inaccurately detected. Usually state-of-the-art systems only work reliably at higher leakage rates. Known leakage detections partly cause a loss of time with and reduction in quality of dialysis treatments.